Certain light fixtures provide light within an illuminated space by projecting the light through an aperture formed in a wall or ceiling. For example, recessed “can” type fixtures have long been in use. These fixtures typically use an incandescent bulb, are mounted within ceiling aperture in a cylindrical housing with an open end, to emit light downwardly through the open end and the aperture, into the illuminated space. Known issues connected with these fixtures include relatively low efficiency/high heat production, and relatively large size connected with the size of typical Edison base bulbs and their corresponding sockets. Compact fluorescent bulbs (CFLs) can be used in these fixtures to improve efficiency, but the fixtures themselves are still sized according to the size of their Edison base, incandescent bulb predecessors.
Recent advances in light-emitting diode (LED) technology have opened up opportunities to retrofit existing installations, and provide new installations, with fixtures that are based on compact and energy efficient light engines. Advanced mechanical apparatus and methods such as those described below can be used to facilitate installation and minimize height of such fixtures.